1. Technical Field
This invention relates to foam materials and, more particularly to a ceramic foam. It also relates to a method of producing a ceramic foam comprising the steps of creating a foam from a pre-ceramic resin; and, heating the resultant resin foam for a time and at a temperature which converts the pre-ceramic resin to a ceramic.
2. Background Art
Various foam materials are known in the art. There are flexible foams such as foam rubber and solid foams such as polystyrene foam. There are closed cell foams, such as polystyrene, which do not absorb water and similar liquids and, therefore, float. There are open cell foams, such as foam rubber, which absorb water and, therefore, are more useful as sponges than as floats.
All the various foams known in the prior art are high temperature intolerant. That is, if heated to high temperatures, they lose their structure, melt, burn, and disintegrate. Thus, they are not useful for such applications as, for example, catalytic converter substrates or for structural applications.
Ceramic materials are able to withstand temperatures that most metals cannot tolerate. It would, also, be desirable to have a way of making an open cell ceramic foam, although closed cell foams can be desirable as well.
Wherefore, it is an object of the present invention to provide a foam material and method of making it which is tolerant to high temperatures such as would be encountered in a catalytic converter of an internal combustion engine or for a structural application.
It is another object of the present invention to provide a foam material made of ceramic and a method of producing it.
It is still another object of the present invention to provide an open and/or closed cell foam material made of ceramic and a method of producing it which is particularly useful as a substrate for the catalyst material in an automotive catalytic converter or for structural application.
Other objects and benefits of this invention will become apparent from the description which follows hereinafter when read in conjunction with the drawing figures which accompany it.